In order to reduce the take-off distance of an aircraft or to improve its take-off performance for a given take-off distance, it is necessary to impart a high vertical speed to the aircraft and to allow it to take up incidence rapidly. Vertical speed is obtained by extending the entire landing gear and the taking up of incidence is mainly related to the extension capacity of the nose landing gear. The extension must take place extremely quickly. In particular, when being catapulted, the nose landing gear must be capable of extending to raise the nose of the aircraft through several hundred millimeters in a very short period of time, about 0.15 seconds.
There exist devices for imparting a high vertical speed to an aircraft or to a portion thereof in order to facilitate very short take-off. Such devices are generally complex and additional to the normal equipment of the aircraft, thus increasing its weight.
Preferred embodiments of the present invention integrate the possibility of imparting high vertical speed to the aircraft or to a portion of the aircraft in one or more of its shock absorbers by providing shock absorbers capable of storing energy and of restituting said energy in a very short period of time.